BackgroundCrisis Concordat was established to improve outcomes for people experiencing a mental health crisis. The Crisis Concordat sets out four stages of the crisis care pathway: (1) access to support before crisis point; (2) urgent and emergency access to crisis care; (3) quality treatment and care in crisis; and (4) promoting recovery.ObjectivesTo evaluate the clinical effectiveness and cost-effectiveness of the models of care for improving outcomes at each stage of the care pathway.Data sourcesElectronic databases were searched for guidelines, reviews and, where necessary, primary studies. The searches were performed on 25 and 26 June 2014 for NHS Evidence, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, NHS Economic Evaluation Database, and the Health Technology Assessment (HTA) and PROSPERO databases, and on 11 November 2014 for MEDLINE, PsycINFO and the Criminal Justice Abstracts databases. Relevant reports and reference lists of retrieved articles were scanned to identify additional studies.Study selectionWhen guidelines covered a topic comprehensively, further literature was not assessed; however, where there were gaps, systematic reviews and then primary studies were assessed in order of priority.Study appraisal and synthesis methodsSystematic reviews were critically appraised using the Risk Of Bias In Systematic reviews assessment tool, trials were assessed using the Cochrane risk-of-bias tool, studies without a control group were assessed using the National Institute for Health and Care Excellence (NICE) prognostic studies tool and qualitative studies were assessed using the Critical Appraisal Skills Programme quality assessment tool. A narrative synthesis was conducted for each stage of the care pathway structured according to the type of care model assessed. The type and range of evidence identified precluded the use of meta-analysis.Results and limitationsOne review of reviews, six systematic reviews, nine guidelines and 15 primary studies were included. There was very limited evidence for access to support before crisis point. There was evidence of benefits for liaison psychiatry teams in improving service-related outcomes in emergency departments, but this was often limited by potential confounding in most studies. There was limited evidence regarding models to improve urgent and emergency access to crisis care to guide police officers in their Mental Health Act responsibilities. There was positive evidence on clinical effectiveness and cost-effectiveness of crisis resolution teams but variability in implementation. Current work from the Crisis resolution team Optimisation and RElapse prevention study aims to improve fidelity in delivering these models. Crisis houses and acute day hospital care are also currently recommended by NICE. There was a large evidence base on promoting recovery with a range of interventions recommended by NICE likely to be important in helping people stay well.Conclusions and implicationsMost evidence was rated as low or very low quality, but this partly reflects the difficulty of conducting research into complex interventions for people in a mental health crisis and does not imply that all research was poorly conducted. However, there are currently important gaps in research for a number of stages of the crisis care pathway. Particular gaps in research on access to support before crisis point and urgent and emergency access to crisis care were found. In addition, more high-quality research is needed on the clinical effectiveness and cost-effectiveness of mental health crisis care, including effective components of inpatient care, post-discharge transitional care and Community Mental Health Teams/intensive case management teams.Study registrationThis study is registered as PROSPERO CRD42014013279.FundingThe National Institute for Health Research HTA programme.